Cruise Control...Surging?

[rb68rr]

What would cause my car to surge back and forth when the cruise control is on. Not going up and down hills, but on a flat road. Thanks, R.B.

 

[Bonden]

Do you by chance hear a little "tic" coming from your speedo head every 1/10 of a mile? These speedos seem to develop problems at higher mileage and the gears can sorta jam every time you go that distance. Mine does this and causes the tranny to drop in and out of lock-up. The speedo still shows speed, but does not record mileage - this occured at 86,000 miles or so. It's bothersome to the point I don't use cruise control at all.

hope this helps

 

[JDEstill]

I had a torque converter that would randomly unlock while cruising along the freeway at constant speed on flat ground. Had to replace it to fix the problem. You might do something to keep the converter unlocked for a while and see if that is the root cause of the problem.

John

 

[RICHIE HIGH PSI]

Does it do it with the a/c on and off?
Rich

 

[Roc87]

Mine surges all the time with the cruise control on, worse at low speeds (60 is worse than 80) I was thinking it might be a bad module causing a vacuum leak. I had replaced all vacuum hoses, so a leak elsewhere is pretty much out of the question.

TTT for ya.

 

[rb68rr]

It does it with the a/c on or off. Doesn't matter. As soon as I disengage the cruise it
stops surging. I thought there might be a vacuum leak somewhere but haven't found one yet. R.B.